/Engine/Source/Runtime/Experimental/GeometryCollectionEngine/Public/GeometryCollection/GeometryCollectionComponent.h
Set the local rest transform, this may be different from the rest collection If the geometry collection is already simulating those matrices will be overriden by the physics state updates
void SetLocalRestTransforms ( const [TArray](API\Runtime\Core\Containers\TArray)< FTransform > & Transforms, bool bOnlyLeaves )